1. Field of the Invention
This invention relates to aqueous hair styling aids, especially hair styling mousses, which incorporate a volatile silicone and which have improved strength and durability of hair hold and superior sensory feel.
2. Background and Prior Art
Hair styling aids such as hair styling mousses provide human hair with a temporary set which can be removed by water or by shampooing, and function by applying a thin film of a resin or gum onto the hair to adhere adjacent hairs together so that they retain the particular shape or configuration at the time of application.
Conventional hair styling mousses typically utilise a hair setting polymer, water, surfactant and propellant gas, with optional adjuvants such as aesthetic agents, fragrance and hair conditioning agents. The conditioning agents used have included silicone-type materials.
EP 0 523 388 discloses an aqueous hair styling aid or mousse composition incorporating a non-volatile silicone compound or other water-insoluble, emulsifiable conditioning agent. The preferred non-volatile silicone compound is a 3:1 mixture of a low molecular weight polydimethylsiloxane fluid and a higher molecular weight polydimethylsiloxane gum.
EP 0 205 306 discloses the use of high molecular weight silicone materials in styling mousses. These are defined as polydiorganosiloxanes having a viscosity of at least 100,000 cst. The high molecular weight silicone is dissolved in the propellant phase prior to filling the aerosol container.
A problem is that those silicone materials which are typically used as conditioning agents in hair care applications tend to make the hair too soft to form and retain a style.
CA 1 214 106 describes that the use of cyclic silicone fluids in ethanol-based aerosol hairspray compositions provides increased holding power and softer feel compared with formulations containing silicone glycols as plasticising materials for the hairspray resin. However this publication is concerned entirely with ethanol-based systems, and none of the formulations disclosed contain any water. Increasingly with the advent of legislation concerning the volatile organic content of hairsprays, it has become desirable to formulate systems with relatively high water content.
EP 0 657 157 A1 discloses that particular volatile linear and cyclic alkylmethylsilicones can be substituted for a portion of the water in a low VOC compliant styling aid formulation, and form compatible systems when combined with water and ethanol in certain prescribed ranges of these three ingredients. This publication is concerned specifically with alkylmethylsilicones having in the molecule methyl and alkyl groups which include six, seven or eight carbon atoms.
The present inventors have surprisingly discovered that the strength and durability of hair hold delivered by a hair styling resin in an aqueous hair styling mousse can be significantly increased by the inclusion in the formulation of certain volatile silicones selected from linear and cyclic dimethylsilicones. Advantageously, hair styling mousses of the invention also exhibit superior sensory feel.